1. Field of the Invention
The present invention relates to lighting systems and more particularly to an illumination assembly with an adjustable direction mounting which uses a directional light source such as light emitting diodes suitable for interior lighting in aviation applications.
2. The Prior Art
Fluorescent lighting systems have been used in general and commercial aviation. Disadvantages of such systems include the cost associated with lamp breakage and the dangers associated with high voltage.
Light emitting diodes (LEDs) as a source of light offer several benefits over fluorescent systems such as solid state reliability, long life, reduced heat dissipation, and reduced energy use, with little or no added weight.
An LED light source is highly directional, providing most light in one orientation as opposed to the continuous radial distribution of light around a fluorescent tube. The combination of mounting, location, filtering and distribution of white LEDs in a multi-LED design is critical to achieving an aesthetic light output. The directional nature of the diodes themselves creates a situation where a slight angular change in installation can significantly change the appearance of lighted areas. Filtering may be employed to convert the color temperature of the light emitted from the diodes to a warmer color temperature as produced by traditional light sources, and to blend the light produced by adjacent LEDs so that variations in color temperature between individual LEDs are not noticeable.
An illumination assembly is provided, for use, for example, as a wash light in aviation applications. In one aspect, the assembly includes a support bracket preferably made from an extruded plastic material, which is adapted for mounting on a support structure. A housing is adjustably connected to the support bracket, an electronic assembly is mounted within the housing, and a directional light source such as an LED light source is mounted on the electronic assembly. A cam follower/locking mechanism is connected to the support bracket and the housing for angularly adjusting the housing to a selected position relative to the support bracket and locking the housing in the selected position.
Preferably, the electronic assembly includes at least one, preferably two elongated circuit boards disposed over and parallel to each other, one of the boards carrying the LED or other directional light source and the other of the boards carrying driving and thermal protection circuitry for the light source.
The electronic assembly may be mounted within the housing via two attached rails which mate with elements or features internal to the housing such that assembly is accomplished by sliding the rails into the receiving elements in the housing.
Preferably, the support bracket includes a cradle which may be cylindrical and the housing includes a tube received by the cradle defining an interior space. The cam follower/locking mechanism preferably extends through a bottom portion of the cradle into the interior space to apply force to rotate the housing. The support bracket preferably includes a plurality of rivets riding in a plurality of circumferential slots in the housing. A longitudinally angled slot is disposed in a lower portion of the housing to permit the housing to rotate up to approximately 110 degrees around an axis of rotation parallel to the length of the support bracket upon application of force by the cam follower/locking mechanism.
The cam follower/locking mechanism preferably includes a headed shaft which engages the longitudinally angled slot, an indicator bracket extending around to a front portion of the support bracket, a knob having a surface interfacing with the indicator bracket and a counter bore for receiving a rubber O-ring captured underneath a washer and a screw.
Preferably, the interface surface of the knob includes an inclined portion and a planer portion having at least two indentations. The indicator bracket preferably includes at least two raised protrusions corresponding to the indentations, which are adapted to rotationally travel along the inclined portion on the knob""s interface surface upon rotation of the knob relative to the indicator bracket and to be received within the indentations.
The support bracket preferably has a flat front surface with markings indicating a series of light direction angles relative to a back mounting surface of the support bracket. The indicator bracket preferably includes a pointer riding along the flat front surface on the support bracket to provide a reading of the light direction angle. A portion of longitudinally angled slot is varied so as to permit fine adjustment around a selected angular position.
In another aspect, an adjustable direction mounting for a directional light source is provided. The mounting includes a support bracket adapted for mounting on a support structure, and a housing adjustably connected to the support bracket. The housing has a longitudinally angled slot in a lower portion of the housing. A shaft is disposed in the longitudinally angled slot for slidable movement relative to the support bracket, and a means is provided for securing the shaft in a selected fixed position.